Topics and links of the broadcast 15-01-2023 11:00 am (CEST)

Technonet changes (PD4Z)

At the request to get more leaders for the technonet broadcasts, I have made myself available for at least 6 technonet broadcasts for 2023.

If this is expected to go well, I will continue this for the time after. I want to make a few changes in order to get straight into it.

First of all, I will make a prize available in my broadcasts with a voucher of 100 Euro (intended to stimulate DIY projects), to be spent at our local radio shop. Everyone who actively registers in my tecnonet rounds has a chance to win. Based on the active participants, the draw will take place after these rounds, under the supervision of the board or technonet leaders. The schedules of my technonet rounds can be found on veron A22 agenda and on this website under the heading radio. Everyone is welcome on the rounds of the technonet, both at home and abroad, as long as you have a valid broadcasting licence.

During these rounds I will also pay attention to a number of innovative techniques and share my findings under the following topics:
- The manufacturing of ceramic materials for radio use at home
- New methodologies for the DIY manufacturing of ferrite composites and related improvements
- Improving the crystal radio using special alloys
- Radio tubes on low voltage
- Manufacturing low cost graphite products voor radio usage
- More to come

All my past experiments I will report and share on this website.

Information from Henk PA0HNB

In addition to research in radio astronomy, LOFAR is also used for other types of research. In the initial phase of LOFAR, researchers in precision agriculture and infrasound were involved. Measuring instruments for measuring infrasound have actually been placed on various LOFAR fields. See, among other things, A publication by the KNMI

Please note that there are more background articles worth reading on the KNMI website for those interested.

Although the measuring instruments are still present at a number of LOFAR fields, not much research is currently being done with them. A subject that is currently receiving a great deal of attention is research into lightning. It turns out that with LOFAR the paths of the rays can be displayed beautifully. This has already led to many new insights. A researcher at ASTRON (and the University of Groningen) has received a large European grant to continue working on this. read more here.

Space weather can also be measured excellently with our LOFAR instrument.

Radio propagation and news (by PC5D)

Propagation news is curated by Tom PC5D. In the composition he makes other use of the information relevant to the Netherlands from the weekly Propagation News of the British radio amateur association RSGB, dxinfocentre , , Make More Miles on VHF and Propagation news is also part of the radio news of the South Limburg Sunday morning round. The audio recording of this round is back listened on


The increase in activity on the sun continued last week. The solar flux here exceeded the 200 limit. With an SFI of more than 200, all HF bands are reliably open and gaps at 6m can also be expected.
Geomagnetic conditions alternated from calm to excited with brisk periods due to a passing coronal mass ejection (CME).

The sun was generally active with the second strongest X-flare of this cycle on Monday (an X1.9), followed by an X1.0 late Tuesday evening. It is therefore not surprising that equally powerful Mögel-Dellinger effects occurred with these strong flames. While not quite enough for a Category S1 proton storm on Friday morning, the recorded proton stream blocked radio wave propagation above the polar ice caps.

Also noteworthy were the newly formed active regions on the eastern edge of the sun. So that ten numbered and three unnumbered spots could be counted on the visible side of the sun on Saturday morning.

Due to the high solar activity of the past week, the maximum usable frequency for a distance of 3000 km regularly exceeded 30 MHz in the afternoon, just like in the previous week. At night it usually dropped to 7 to 9 MHz, sometimes even below. For the next few days, NOAA expects a Kp index of 2 or 3 and flares of M and possibly X class. The solar flux index will be around 210-215, but it will probably drop a lot lower again by the end of the week. The speed of the solar wind was moderately high on Saturday at 515 km/s with the prospect that Earth could still be hit sideways by a recent CME. Combined with the ongoing solar flares, the probability of a minor radio blackout is 55%. If this happens, expect the MUF to take a dip, maybe only for 20 minutes to an hour and especially negative effects on the lower HF bands: At 160 and 80 meters signals should then have a very difficult time crossing the polar zones.

We are still in winter, with little solar radiation in the northern hemisphere. The attenuating D layer is mainly fed by many short UV and X-ray flashes from more intense solar flares. A reduction in the bursts of flames would be the typical restore good propagation conditions in winter at 160 and 80 meters. Without attenuating the good daytime propagation conditions at the higher frequencies.


There will be some changes in the weather pattern in the coming days. Nearby low-pressure areas, however, remain dominant with the necessary wind and somewhat lower temperatures. Unfortunately, no chance of significant tropo conditions this week either. In terms of propagation, it seems that rain or snow spread for the GHz bands will be the most likely mode.

The Dourbes charts on show a strong Sporadic-E at times, but we are approaching the end of the midwinter Es window this week. Still, that layer in the VHF range can still provide openings. For example, EI7GL reports a transatlantic opening at 40 MHz on Friday, January 13. For meteor scatter there are random and the small Gamma-Ursae-Minorids with a low maximum on the 18th. For Aurora, the Kp index is too low for the time being, but then it can change depending on the activity on the sun. Ideally it should be five or rather higher for auroras.

The Moon reaches maximum negative declination next Thursday, and perigee on Saturday, so EME path losses are low and Moon availability windows are short. 144MHz celestial clutter increases throughout the week, peaking at over 2000 Kelvin on Thursday.